1. Field of the Invention
The present invention relates to a function module, and in particular to a function module with built-in heat dissipation device.
2. Description of the Related Art
As semiconductor process technology has developed, the operating speeds thereof increased accordingly, such that a single electronic device may incorporate multiple functions. However, due to such designs, it is difficult to simultaneously control heat dissipation, signal quality, and electromagnetic radiation in the electronic device.
Generally, electronic devices communicate via a printed circuit board (PCB). In a computer system, electronic devices, such as a central processor unit (CPU), a chipset, a graphics processing unit (GPU), an accelerated graphics port (AGP), or dynamic random access memory (DRAM), are disposed on different areas of a motherboard. To solve heat dissipation problems for each electronic device, a conventional solution is provided for each electronic device.
For example, a combination of a heat dissipation fin, a heat pipe, and a fan is usually used for the CPU. The heat dissipation fin and/or the fan are usually used for the chipset or the GPU. As shown in FIG. 1, a conventional heat dissipation device 20 of a notebook computer including a heat conduction layer 21, a heat pipe 22, a heat dissipation fin 23, and a fan 24 is used to dissipate heat for a device 10 such as a CPU. The heat dissipation device 20 operates as follows: first, the heat conduction layer 21 is abutted against the device 10 to conduct heat from the device 10 to a larger area such that heat density is reduced; next, the heat pipe 22 guides heat from the heat conduction layer 21 to the heat dissipation fin 23 at a further end; finally, airflow is produced by the fan 24, following the direction of arrows A and B through the heat dissipation fin 23, and thus, heat is carried away from the heat dissipation fin 23 by the airflow.
The heat dissipation device 20 is challenged by thermal resistance from heat conduction and heat convection. The thermal resistance of heat conduction includes contact resistance between the device 10 and the heat conduction layer 21, diffusion resistance of the heat conduction layer 21, contact resistance between the heat conduction layer 21 and the heat pipe 22, thermal resistance of the heat pipe 22, contact resistance between the heat pipe 22 and the heat dissipation fin 23, and diffusion resistance of the heat dissipation fin 23. Additionally, the airflow produced by the fan 24, attempting to carry heat away from the heat dissipation fin 23, generates the thermal resistance of heat convection.
As mentioned above, the conventional heat dissipation device 20 is challenged by thermal resistance of heat conduction and convection. To effectively solve the heat dissipation problem of a motherboard with a plurality of electronic devices thereon, a heat dissipation device with better efficiency is required to increase heat conduction and dissipation and minimize thermal resistance thereof.